chapman



' (No Model.) J. H. NEWBURY 8?; G. A. CHAPMAN.

DEVICE FOR THRBADING PLUGS. No 259,903. Patented June 20,1882

Fig, 1;

4 mum;

2 III UNITED STATES PATENT OFFICE.

JAY H. NEWBURY AND GEORGE A. CHAPMAN, OF GOXSAOKIE,'NEW YORK.

DEVICE FOR THREADING PLUGS.

SPECIFICATION formingpart of Letters latent No. 259,903, dated June 20, 1882,

I Application filed March 25,1882. (No model.)

To all whom tt may concern Be it known that we, JAY H. NEWBURY and GEORGE A. CHAPMAN, of Goxsackie, in the county of Greene and State of New York, have invented certain new and useful Improvements in Devices for Threading Plugs; and we do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings,

which form a part of this specification.

Figure 1 is a longitudinal sectional view, showing our improved plug-holder in position in a turning-lathe. Fig. 2 isa perspective view of the holder detached. Fig. 3 is a perspective View of one of the plugs before being threaded. Fig. 4 is a sectional view of thesame after being threaded. Fig. 5 is a plan view of the thread cutter or chaser.

Corresponding parts in the several figures are denoted by like letters of reference.

This invention has for its object to facilitate the threading of plugs for gas, steam, and water pipe fittings, as will be hereinafter more fully described.

A in the drawings represents one of the plugs to be threaded. These plugs are made of castiron or other suitable material, and they consist of a tapering shell, B, provided with a square butt or head, 0.

D is the shank or holder, which is made of iron, and consists of a simple cylindrical rod of suitable dimensions, and provided at one end with a trul-ycentered recess or depression, E, to receive the spindle Fof the face-plate G of an ordinary iron-turning lathe, from which it is driven by a dog or carrier, H,of the usual well-known construction. In the other end of the shank, which is in practice supported on the live center or rest I, is formed a counter sink, J ,.to receive the head 0 of the plug to be threaded. The dead-center of the lathe K is then screwed up to thecountersink inthe hollow partor shell of the plug, holding it very securely while being threaded. The dead-center of the lathe is adjusted to one side, so as to give the required taper to the plug.

' Lrepresents the chasing-tool, which is placed in the tool-rest and fed by the ordinary gear, the feed being regulated according to the pitch of the thread. When the thread has been cut the lathe is stopped and thefecd-nut opened, which allows the rest to be moved back to the starting-point. The plug which has just been threaded is then taken out and another placed in position ready to undergo the same operation.

This class of plugs have heretofore been either threaded with a die or placed in a chuck and threaded with an ordinary lathe-tool. By either method much time is lost, which by our invention may be saved.

' Having thus described our invention, we claim and desire to secure by Letters Patent of the United States- The combination, with the lathe, dog, and rest I, of the shank or holder D, havingcentered recess E at one end and square recess J at the other, constructed as herein described, as and for the purpose set forth.

In testimony that we claim the foregoing as our own we have hereto affixed our signatures in presence of two witnesses.

JAY H. NEWBURY. GEORGE A. CHAPMAN.

Witnesses:

EDGAR (J. MooN, FRANK MOSHER. 

